lib/strings+test: 0-arg trim strips ASCII whitespace per Hare

The 0-arg ltrim/rtrim/trim used to return input unchanged. Hare's
0-arg form strips [' ', '\n', '\t', '\r'] (ref/hare/strings/trim.ha:6).
Aligned by delegating to bytes.ltrim/bytes.rtrim with the whitespace
set spread inline at the call site — the obvious `let ws = whitespace[0:4]`
shape produces a slice whose ptr does NOT alias storage (#40).
N-arg forms (strip-specific-runes) untouched.

Test rows retargeted to Hare's canonical inputs from trim.ha:78/85
so '\r' is exercised alongside ' '/'\t'/'\n'.

lib/strings/strings.ww

@@ -3,10 +3,6 @@
 //
 // Documented divergences from Hare:
 //
-//   - `trim` / `ltrim` / `rtrim` 0-arg returns the input unchanged.
-//     Hare strips ASCII whitespace via `bytes::ltrim(input,
-//     whitespace...)`; that needs `lib/bytes` variadic graduation
-//     (future commit).
 //   - `byteindex` / `rbyteindex` rune arms encode via
 //     `utf8.encoderune`; the legacy impls scanned for `r: u8` (an
 //     undocumented ASCII-only restriction that silently dropped
@@ -402,12 +398,21 @@ export fn trimsuffix(input: str, suffix: str) str = {
 	return r;
 };
 
+// whitespace — ASCII whitespace set used by the 0-arg ltrim/rtrim/trim
+// branches (#9). ref/hare/strings/trim.ha:6.
+let whitespace: [4]u8 = [0x20u8, 0x0Au8, 0x09u8, 0x0Du8];
+
 // ltrim — strip leading runes that occur in `trim`. Borrowed view.
-// Empty `trim` returns input unchanged (Hare's no-rune branch strips
-// ASCII whitespace via `bytes::ltrim`; needs lib/bytes variadic
-// graduation). ref/hare/strings/trim.ha:11.
+// 0-arg strips ASCII whitespace via [[bytes.ltrim]] (#9).
+// ref/hare/strings/trim.ha:11. The spread expression is inlined
+// because `let ws: []u8 = whitespace[0:4]` produces a slice whose
+// ptr doesn't track the module-level array storage (filed as #40);
+// `b.flush = flushdefault[0:1]` in lib/bufio is the same shape via
+// the working field-assign path.
 export fn ltrim(input: str, trim: rune...) str = {
-	if (trim.len == 0) { return input; };
+	if (trim.len == 0) {
+		return fromutf8_unsafe(bytes.ltrim(toutf8(input), whitespace[0:4]...));
+	};
 	let it: iterator = iter(input);
 	for (true) {
 		match (next(&it)) {
@@ -433,9 +438,13 @@ export fn ltrim(input: str, trim: rune...) str = {
 };
 
 // rtrim — strip trailing runes that occur in `trim`. Borrowed view.
+// 0-arg strips ASCII whitespace via [[bytes.rtrim]] (#9). Spread is
+// inlined to dodge #40 — see [[ltrim]].
 // ref/hare/strings/trim.ha:32.
 export fn rtrim(input: str, trim: rune...) str = {
-	if (trim.len == 0) { return input; };
+	if (trim.len == 0) {
+		return fromutf8_unsafe(bytes.rtrim(toutf8(input), whitespace[0:4]...));
+	};
 	let it: iterator = riter(input);
 	for (true) {
 		match (next(&it)) {

lib/strings/stringstest.ww

@@ -446,9 +446,8 @@ fn streq(a: str, b: str) bool = {
 };
 
 // ---- ltrim / rtrim / trim ---------------------------------------------
-// ref/hare/strings/trim.ha:75-97. Bytes.ltrim whitespace-default rows
-// (`ltrim("  hi") == "hi"`, etc.) deferred — they need lib/bytes
-// variadic graduation.
+// ref/hare/strings/trim.ha:75-97. 0-arg rows (#9) pin the ASCII
+// whitespace set (' ', '\t', '\n', '\r' — ref/hare/strings/trim.ha:6).
 
 @test fn ltrim_cases() void = {
 	let runes: [9]rune;
@@ -462,10 +461,12 @@ fn streq(a: str, b: str) bool = {
 	runes[7] = 'c';
 	runes[8] = 'd';
 
-	let inputs: [8]str;
-	let argo:   [8]i32;
-	let argn:   [8]i32;
-	let want:   [8]str;
+	// 0-arg rows (8..10) strip ASCII whitespace per Hare (#9):
+	// only the leading side is stripped for ltrim.
+	let inputs: [11]str;
+	let argo:   [11]i32;
+	let argn:   [11]i32;
+	let want:   [11]str;
 	inputs[0]="";              argo[0]=0; argn[0]=1; want[0]="";
 	inputs[1]="aaabc";         argo[1]=1; argn[1]=1; want[1]="bc";
 	inputs[2]="xyz";           argo[2]=1; argn[2]=1; want[2]="xyz";
@@ -474,9 +475,12 @@ fn streq(a: str, b: str) bool = {
 	inputs[5]="((()(())))())"; argo[5]=3; argn[5]=2; want[5]="";
 	inputs[6]="abacadabra";    argo[6]=5; argn[6]=4; want[6]="ra";
 	inputs[7]="hello";         argo[7]=0; argn[7]=0; want[7]="hello";
+	inputs[8]=" hello ";       argo[8]=0; argn[8]=0; want[8]="hello ";
+	inputs[9]="\t\r\n  hello"; argo[9]=0; argn[9]=0; want[9]="hello";
+	inputs[10]="  ";           argo[10]=0; argn[10]=0; want[10]="";
 
 	let i: i32 = 0;
-	for (i < 8) {
+	for (i < 11) {
 		signalled = 1100 + i;
 		let argv: []rune;
 		argv.ptr = &runes[argo[i]];
@@ -510,10 +514,12 @@ fn streq(a: str, b: str) bool = {
 	runes[17] = 'a';
 	runes[18] = 'd';
 
-	let inputs: [8]str;
-	let argo:   [8]i32;
-	let argn:   [8]i32;
-	let want:   [8]str;
+	// 0-arg rows (8..10) strip ASCII whitespace per Hare (#9):
+	// only the trailing side is stripped for rtrim.
+	let inputs: [11]str;
+	let argo:   [11]i32;
+	let argn:   [11]i32;
+	let want:   [11]str;
 	inputs[0]="";        argo[0]=0; argn[0]=1; want[0]="";
 	inputs[1]="bcaaa";   argo[1]=1; argn[1]=1; want[1]="bc";
 	inputs[2]="xyz";     argo[2]=1; argn[2]=1; want[2]="xyz";
@@ -524,9 +530,13 @@ fn streq(a: str, b: str) bool = {
 	inputs[6]="Sentimentalized sensationalism sensationalized sentimentalisms";
 	                     argo[6]=7; argn[6]=12; want[6]="S";
 	inputs[7]="hello";   argo[7]=0; argn[7]=0; want[7]="hello";
+	inputs[8]=" hello "; argo[8]=0; argn[8]=0; want[8]=" hello";
+	inputs[9]="hello, world\r\n\r\n";
+	                     argo[9]=0; argn[9]=0; want[9]="hello, world";
+	inputs[10]="  ";     argo[10]=0; argn[10]=0; want[10]="";
 
 	let i: i32 = 0;
-	for (i < 8) {
+	for (i < 11) {
 		signalled = 1200 + i;
 		let argv: []rune;
 		argv.ptr = &runes[argo[i]];
@@ -549,10 +559,12 @@ fn streq(a: str, b: str) bool = {
 	runes[6] = '[';
 	runes[7] = ']';
 
-	let inputs: [7]str;
-	let argo:   [7]i32;
-	let argn:   [7]i32;
-	let want:   [7]str;
+	// 0-arg rows (7..9) strip ASCII whitespace per Hare (#9) from
+	// both ends.
+	let inputs: [10]str;
+	let argo:   [10]i32;
+	let argn:   [10]i32;
+	let want:   [10]str;
 	inputs[0]="";            argo[0]=0; argn[0]=1; want[0]="";
 	inputs[1]="aaabcaaa";    argo[1]=1; argn[1]=1; want[1]="bc";
 	inputs[2]="xyz";         argo[2]=1; argn[2]=1; want[2]="xyz";
@@ -561,9 +573,12 @@ fn streq(a: str, b: str) bool = {
 	inputs[5]="[[][[[]]][][].[[]][]]][]]]";
 	                         argo[5]=6; argn[5]=2; want[5]=".";
 	inputs[6]="hello";       argo[6]=0; argn[6]=0; want[6]="hello";
+	inputs[7]=" hello ";     argo[7]=0; argn[7]=0; want[7]="hello";
+	inputs[8]="\r\thello\n\r"; argo[8]=0; argn[8]=0; want[8]="hello";
+	inputs[9]="  ";          argo[9]=0; argn[9]=0; want[9]="";
 
 	let i: i32 = 0;
-	for (i < 7) {
+	for (i < 10) {
 		signalled = 1300 + i;
 		let argv: []rune;
 		argv.ptr = &runes[argo[i]];

selfhost/cmd/w6c/main.combined.ww

@@ -1840,10 +1840,6 @@ export fn position(d: *decoder) i32 = {
 //
 // Documented divergences from Hare:
 //
-//   - `trim` / `ltrim` / `rtrim` 0-arg returns the input unchanged.
-//     Hare strips ASCII whitespace via `bytes::ltrim(input,
-//     whitespace...)`; that needs `lib/bytes` variadic graduation
-//     (future commit).
 //   - `byteindex` / `rbyteindex` rune arms encode via
 //     `utf8.encoderune`; the legacy impls scanned for `r: u8` (an
 //     undocumented ASCII-only restriction that silently dropped
@@ -2239,12 +2235,21 @@ export fn trimsuffix(input: str, suffix: str) str = {
 	return r;
 };
 
+// whitespace — ASCII whitespace set used by the 0-arg ltrim/rtrim/trim
+// branches (#9). ref/hare/strings/trim.ha:6.
+let whitespace: [4]u8 = [0x20u8, 0x0Au8, 0x09u8, 0x0Du8];
+
 // ltrim — strip leading runes that occur in `trim`. Borrowed view.
-// Empty `trim` returns input unchanged (Hare's no-rune branch strips
-// ASCII whitespace via `bytes::ltrim`; needs lib/bytes variadic
-// graduation). ref/hare/strings/trim.ha:11.
+// 0-arg strips ASCII whitespace via [[bytes.ltrim]] (#9).
+// ref/hare/strings/trim.ha:11. The spread expression is inlined
+// because `let ws: []u8 = whitespace[0:4]` produces a slice whose
+// ptr doesn't track the module-level array storage (filed as #40);
+// `b.flush = flushdefault[0:1]` in lib/bufio is the same shape via
+// the working field-assign path.
 export fn ltrim(input: str, trim: rune...) str = {
-	if (trim.len == 0) { return input; };
+	if (trim.len == 0) {
+		return fromutf8_unsafe(bytes.ltrim(toutf8(input), whitespace[0:4]...));
+	};
 	let it: iterator = iter(input);
 	for (true) {
 		match (next(&it)) {
@@ -2270,9 +2275,13 @@ export fn ltrim(input: str, trim: rune...) str = {
 };
 
 // rtrim — strip trailing runes that occur in `trim`. Borrowed view.
+// 0-arg strips ASCII whitespace via [[bytes.rtrim]] (#9). Spread is
+// inlined to dodge #40 — see [[ltrim]].
 // ref/hare/strings/trim.ha:32.
 export fn rtrim(input: str, trim: rune...) str = {
-	if (trim.len == 0) { return input; };
+	if (trim.len == 0) {
+		return fromutf8_unsafe(bytes.rtrim(toutf8(input), whitespace[0:4]...));
+	};
 	let it: iterator = riter(input);
 	for (true) {
 		match (next(&it)) {

selfhost/cmd/wwdump/main.combined.ww

@@ -1840,10 +1840,6 @@ export fn position(d: *decoder) i32 = {
 //
 // Documented divergences from Hare:
 //
-//   - `trim` / `ltrim` / `rtrim` 0-arg returns the input unchanged.
-//     Hare strips ASCII whitespace via `bytes::ltrim(input,
-//     whitespace...)`; that needs `lib/bytes` variadic graduation
-//     (future commit).
 //   - `byteindex` / `rbyteindex` rune arms encode via
 //     `utf8.encoderune`; the legacy impls scanned for `r: u8` (an
 //     undocumented ASCII-only restriction that silently dropped
@@ -2239,12 +2235,21 @@ export fn trimsuffix(input: str, suffix: str) str = {
 	return r;
 };
 
+// whitespace — ASCII whitespace set used by the 0-arg ltrim/rtrim/trim
+// branches (#9). ref/hare/strings/trim.ha:6.
+let whitespace: [4]u8 = [0x20u8, 0x0Au8, 0x09u8, 0x0Du8];
+
 // ltrim — strip leading runes that occur in `trim`. Borrowed view.
-// Empty `trim` returns input unchanged (Hare's no-rune branch strips
-// ASCII whitespace via `bytes::ltrim`; needs lib/bytes variadic
-// graduation). ref/hare/strings/trim.ha:11.
+// 0-arg strips ASCII whitespace via [[bytes.ltrim]] (#9).
+// ref/hare/strings/trim.ha:11. The spread expression is inlined
+// because `let ws: []u8 = whitespace[0:4]` produces a slice whose
+// ptr doesn't track the module-level array storage (filed as #40);
+// `b.flush = flushdefault[0:1]` in lib/bufio is the same shape via
+// the working field-assign path.
 export fn ltrim(input: str, trim: rune...) str = {
-	if (trim.len == 0) { return input; };
+	if (trim.len == 0) {
+		return fromutf8_unsafe(bytes.ltrim(toutf8(input), whitespace[0:4]...));
+	};
 	let it: iterator = iter(input);
 	for (true) {
 		match (next(&it)) {
@@ -2270,9 +2275,13 @@ export fn ltrim(input: str, trim: rune...) str = {
 };
 
 // rtrim — strip trailing runes that occur in `trim`. Borrowed view.
+// 0-arg strips ASCII whitespace via [[bytes.rtrim]] (#9). Spread is
+// inlined to dodge #40 — see [[ltrim]].
 // ref/hare/strings/trim.ha:32.
 export fn rtrim(input: str, trim: rune...) str = {
-	if (trim.len == 0) { return input; };
+	if (trim.len == 0) {
+		return fromutf8_unsafe(bytes.rtrim(toutf8(input), whitespace[0:4]...));
+	};
 	let it: iterator = riter(input);
 	for (true) {
 		match (next(&it)) {

selfhost/test/smoke.combined.ww

@@ -1731,10 +1731,6 @@ export fn position(d: *decoder) i32 = {
 //
 // Documented divergences from Hare:
 //
-//   - `trim` / `ltrim` / `rtrim` 0-arg returns the input unchanged.
-//     Hare strips ASCII whitespace via `bytes::ltrim(input,
-//     whitespace...)`; that needs `lib/bytes` variadic graduation
-//     (future commit).
 //   - `byteindex` / `rbyteindex` rune arms encode via
 //     `utf8.encoderune`; the legacy impls scanned for `r: u8` (an
 //     undocumented ASCII-only restriction that silently dropped
@@ -2130,12 +2126,21 @@ export fn trimsuffix(input: str, suffix: str) str = {
 	return r;
 };
 
+// whitespace — ASCII whitespace set used by the 0-arg ltrim/rtrim/trim
+// branches (#9). ref/hare/strings/trim.ha:6.
+let whitespace: [4]u8 = [0x20u8, 0x0Au8, 0x09u8, 0x0Du8];
+
 // ltrim — strip leading runes that occur in `trim`. Borrowed view.
-// Empty `trim` returns input unchanged (Hare's no-rune branch strips
-// ASCII whitespace via `bytes::ltrim`; needs lib/bytes variadic
-// graduation). ref/hare/strings/trim.ha:11.
+// 0-arg strips ASCII whitespace via [[bytes.ltrim]] (#9).
+// ref/hare/strings/trim.ha:11. The spread expression is inlined
+// because `let ws: []u8 = whitespace[0:4]` produces a slice whose
+// ptr doesn't track the module-level array storage (filed as #40);
+// `b.flush = flushdefault[0:1]` in lib/bufio is the same shape via
+// the working field-assign path.
 export fn ltrim(input: str, trim: rune...) str = {
-	if (trim.len == 0) { return input; };
+	if (trim.len == 0) {
+		return fromutf8_unsafe(bytes.ltrim(toutf8(input), whitespace[0:4]...));
+	};
 	let it: iterator = iter(input);
 	for (true) {
 		match (next(&it)) {
@@ -2161,9 +2166,13 @@ export fn ltrim(input: str, trim: rune...) str = {
 };
 
 // rtrim — strip trailing runes that occur in `trim`. Borrowed view.
+// 0-arg strips ASCII whitespace via [[bytes.rtrim]] (#9). Spread is
+// inlined to dodge #40 — see [[ltrim]].
 // ref/hare/strings/trim.ha:32.
 export fn rtrim(input: str, trim: rune...) str = {
-	if (trim.len == 0) { return input; };
+	if (trim.len == 0) {
+		return fromutf8_unsafe(bytes.rtrim(toutf8(input), whitespace[0:4]...));
+	};
 	let it: iterator = riter(input);
 	for (true) {
 		match (next(&it)) {